Rotary furnace



Dec. 24, 1946. HOK 2,413,231

ROTARY FURNACE Filed Dec. s, 1943 4 Sheets-Sheet 1 IN VEN TOR.

Kenneth 12. Hoke ZLM 24 A t f Dec. 24, 1946.

K. D. HOKE ROTARY FURNACE Filed Dec. 3, 1943 4 Sheets-Sheet 2 II I INVENTOR.

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Dec. 24, 1946. HQKE 2,4135231 ROTARY FURNACE Filed Dec. 3, 1943 4 Sheets-Sheet 4 mmvrox KenneZ'hDHoke Patented Dec. 24, 1946 ROTARY FURNACE Kenneth D. Hoke, Chicago, Ill., assignor to Fisher Furnace Company, Chicago, 111;, a corporation of Illinois Application December 3, 1943, Serial No. 512,726

4 Claims.

This invention relates to furnaces and retorts and particularly to furnaces for melting both ferrous and nonferrous metals in foundry operations.

An object of the invention is to furnace or retort.

Another object of the invention is to provide a tiltable furnace or retort.

A further object of the invention is to provide a furnace or retort which can be either tilted or rotated or which can be simultaneously tilted or rotated.

Still another object of 'the invention is to provide a rotary furnace or retort which can be tilted without substantially changing the position of the pouring spout.

A still further object of the invention is to provide novel means for tilting a furnace.

Other objects of the invention will be revealed by the following description and the drawings, of which Figure 1 is a side elevational view of a furnace constructed in accordance with my invention;

Figure 2 is a plan view of the furnace shown in Figure 1;

Figure 3 is a front elevational view of the furnace;

Figure 4 is a view partly in elevation and partly in cross-section taken along the line 44 of Figure 1, looking toward the front of the furnace;

Figure 5 is a rear elevational view of the furnace; and

Figure 6 is an enlarged perspective view of a portion of the supporting frame and of a plate cam fastened thereto.

Referring to the drawings, the numeral indicates a horizontal type rotary furnace having an outer steel shell 2 and a lining 3 (Fig. 4), of refractory brick. The furnace is 'cylindricallyshaped with the longitudinal axis thereof lying in a horizontal plane. The front end 5 of the furnace is frusto-conical and has a semi-circular opening 1 adapted to be closed by a semi-circular door 8 adapted to swing open on hinges 9, mounted on stud Ill. The front end of the furnace is provided with a V-shaped pouring provide a rotary spout slightly below the longitudinal axis of the furnace. The door 8 has an arch-shaped opening l2 immediately above the pouring spout. The opening l2 together with the pouring spout N forms an outlet for the furnace gases. The door is provided with a boss l3 which is adapted to cooperate with clamp l5 to hold the door in closed position. The clamp I5 is pivotally mounted on the stud I! welded to the front of the furnace and is provided with a handle l9 to enable the clamp to be opened and closed manually.

Surrounding the furnace intermediate the front and rear thereof are two spaced parallel circular tracks 2 I. The tracks are welded to the outer shell of the furnace. The tracks are held in spaced relation by means of tie-bars 23 which are welded to the furnace shell and to the tracks.

The rear wall of the furnace has a small opening 25 (Fig. 2) in the center thereof. Mounted opposite the opening 25 is a gas or oil burner 21 supplied with fuel through line 28 and with air through lines 29 and 3|, Air is forced into the burner under pressure by means of blower 33 operated by electric motor 35. A regulator 36 is placed in the fuel line to automatically regulate the amount of gas or oil fed to the burner in accordance with the air pressure in line 29.

The air blower, motor, burner and connecting pipes are all mounted on a stationary steel frame indicated generally by the numeral 31. The frame 37 has two spaced parallel hollow rectangular beams 39 and 4|, one on either side of the furnace, held together by two I-beams 43 which are welded thereto. Adjacent the front ends of the two beams 39 and 4| are mounted two vertical posts 45 and 41. Angle pieces 49, 50 and 5| are Welded'to the posts and to the stationary frame to help support the posts.

The upper ends of the posts 45 and 41 are provided with bearings 53 in which are mounted pins or studs 55. A frame, indicated generally by the numeral 51 is pivotally supported on the studs 55 by means of arms 59. As is more clearly shown in Figures 1 and 6, the arms 59 extend from the studs 55 diagonally downwardly and are welded to the top of horizontal hollow rectangular beams 6| which extend rearwardly to a point behind the rams or jacks 63. Two spaced horizontally disposed I-beams are supported below the furnace l by angle pieces 61 Welded to the beams GI and to the top of the I-beams 65. A horizontally disposed channel 69 is welded to the ends of each I-beam 65, perpendicular theretmand extends rearwardly to the jacks or rams 63. When the furnace is in horizontal position, the back ends of the channels 69 are adapted to rest on the top of an I-beam H which extends from beam 39 to beam 4| and is welded to the tops thereof.

Flanged rollers 13 are mounted on two parallel shafts or axles 15 which in turn are mounted in bearings 11 (Fig. 3) supported by or bolted to the tops of angle pieces 61. Each shaft 15 has two spaced rollers 13 mounted thereon on which tracks 2| are adapted to rest. The rollers 13 are rotated by means of belts 19 which pass around pulleys 8| keyed to the shafts 15, intermediate the flanged wheels, and which are adapted to be driven by motor 83 through gear reduction mechanism 85. The gear reduction and motor are supported on a bracket 81 mounted on the frame 51 below the furnace.

The tracks 2| on the furnace are made of rolled angles and are welded to the shell of the furnace so that one face of the angle is concentric with and spaced from the periphery of the furnace. The open side of the rear track faces toward the rear of the furnace and the open side of 'the front track faces toward the front of the furnace.

A small wheel 89 is rotatably supported on a pin 9| which in turn is mounted in bracket 93 fastened to rear I-beam 65. The wheel 89 is adapted to roll on the inside surface of the rear track 2| and functions to prevent the furnace from upsetting when the furnace is tilted upwardly. The flanges on the rollers 13 prevent the furnace from slipping from the rollers when the furnace is tilted.

-A plate cam 95 having flanges e1 extending around a portion thereof, is welded to each of the beams 6| between the posts 41 and the jacks or rams 63. The surface of jacent the ram or jack is curved convexly. Each plate cam 95 lies in the same vertical plane as the post 41 and the jack 63 on the same side of the furnace.

The bottom of the ram or jack 63 on each side of the furnace is welded to the upper surface of I-beam I. Each ram comprises generally a cylinder 98 having an inlet and outlet (not shown) to admit fluid to and eject fluid from the cylinder below the piston, a piston (not shown) and a piston rod 99 On the top of which is mounted a bifurcated bracket in which is rotatedly mounted a wheel 103 having two spaced grooves. Two strands of wire cable 565 are fastened to a plate I01 welded to the plate cam on the lower surface thereof and pass over the surface of the cam adjacent the hydraulic jack, then over the grooves in the wheels I03 and are fastened to. the beams 39 and 4| at the points I09.

By placing spout the pouring spout remains substantially at the same point in all tilted positions of the furnace. .By tying the cable to the cam at a point adjacent the front end of the furnace, it is possible to tilt the furnace to an angle of 45 degrees by raising the piston ram only 1 /2 inches.

Furnaces constructed in accordance with my invention may be of any desired size. For foundry use, I have found that a furnace having a drum of approximately '7 feet in length, 46 inches outside diameter and 36 inches inside diameter is satisfactory. The speed or rotation of the drum. may be varied. A furnace built in accordance with my invention was made to rotate at a speed of. three revolutions per minute. Temperatures up to 3000 F. may be attained in. the furnace so that it may be used for melting ferrous as well as non-ferrous metals. The maximum stroke of the ram piston is 1 /2 inches.

When pouring the furnace the rotation of the furnace drum is stopped so that the pouring spout is in the position shown in Figure 3. The furnace is then tilted to a position in which metal will run out of. the spout; As the? pouring progresses the furnace is gradually tilted to agreater angle. When pouringis completed the furnace the plate cam 95 adthe pivots 53 adjacentthe pouring is returned to the horizontal position, the front door is opened and the furnace charged with solid metal ingots or scrap metal or both. Rotation and heating are then resumed.

It will be seen, therefore, that I have succeeded in constructing a strong, compact furnace unit which can be both rotated and tilted by mechanical or power means. The furnace lends itself to rapid melting and pouring without spilling of the molten metal.

Although we have shown the burner mechanism mounted on the stationary frame, it will be understood that the burner mechanism can be mounted on the tiltable frame so that it will tilt with the furnace. Where the burner mechanism is mounted on the tiltable frame, it is merely necessary to provide flexible connections to the fuel supply.

It is claimed:

1. An internally heated melting furnace comprising a stationary support, a tiltable carriage pivotally mounted adjacent its front end on said support, said carriage being provided with at least two spaced sets of rollers, a horizontal, cylindrical crucible having at least two spaced apart tracks around the periphery thereof, each track being adapted to rest on a set of said rollers, said crucible being rotatable and loosely mounted on said rollers, means for causing said crucible to rotate, means for tilting said carriage and crucible, the track adjacent the rear end of the crucible having a fiat under surface concentric with and spaced from the periphery of the crucible, a roller mounted on the carriage below the crucible between said under surface of said track and the periphery of the crucible in order to prevent said crucible from upsetting when said carriage is tilted.

2. A horizontally disposed internally heated furnace mounted on a frame which is pivotally supported adjacent the pouring spout of said furnace, said frame being provided with a plurality of sets of power operated flanged rollers, said furnace being equipped with a plurality of spaced peripheral tracks adapted to loosely rest on said rollers, a roller mounted on the lower rear portion of said frame and adapted to ride on thesurface of the rearmost track, opposite from the surface which rides on said supporting rollers, in order to prevent the furnace from toppling from the frame when the frame is tilted, a pair of downwardly inclined arms rigidly mounted on the frame and extending rearwardly from the points of pivotal support, a pair of hydraulic jacks vertically mounted on either side of said furnace intermediate the front and rear ends thereof, a rotatable wheel mounted on the top of each jack, and a cable fastened to each of said arms at a point between the pivotal support and said jack said cable passing over the roller of the jack on the same side of the furnace and the other end of the cable being fastened to a stationary point below said last mentioned roller.

3. A horizontally disposed rotatable and tiltable, internally heated furnace mounted-on s.- carriage which is pivotally supported adjacent the pouring spout of said furnace said carriage being provided with a plurality of spaced sets of rollers, said furnace being equipped with a plu-- rality' of spaced peripheral tracks adapted to loosely rest on saidrollers, means torotate said furnace on said rollers, means to preventsaid furnace from falling from said carriage whenthe furnace is tilted, a pair of downwardly in clined' arms rigidly mounted on the carriage and.

extending rearwardly from the points of pivotal support, a pair of jacks vertically mounted on either side of said furnace intermediate the front and rear ends thereof, a rotatable wheel mounted on the top of each jack, a cable fastened to each 5 of said arms at a point between the pivotal support and said jack, said cable passing over the roller of the jack on the same side of the furnace and being fastened to a. stationary point below said roller on the side of said jack opposite to the 10 aforesaid point on said arms.

KENNETH D. HOKE. 

